Ensure all dependencies are installed on travis.

Author: Felix Arntz

.travis.yml

@@ -22,6 +22,9 @@ matrix:
 
 before_script:
   - composer install
+  - cd php52
+  - composer install
+  - cd ..
   - npm install
   - bash tests/bin/install-wp-tests.sh wordpress_test root '' localhost $WP_VERSION
   - export PATH="$HOME/.composer/vendor/bin:$PATH"